New Hampshire Cosmetology Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The primary ingredient in a basic shampoo formula is surfactants. Surfactants play a crucial role because they are responsible for the cleansing action in shampoos. They lower the surface tension between water and oils, allowing the shampoo to emulsify and lift dirt, oil, and impurities from the hair and scalp. When you apply shampoo, the surfactants work to create lather, which further aids in the cleaning process, making it easier to rinse away debris and excess oils.

In addition to surfactants, other components like conditioners, colorants, and thickeners can be added to enhance the shampoo's performance or aesthetic appeal; however, they do not serve the primary function of cleaning the hair. Conditioners are included to soften and detangle hair, colorants can alter the appearance of the product, and thickeners help improve the texture and consistency, but none of these fulfill the essential role of surfactants in a shampoo.